Marijuana plants grow at Perennial Holistic Wellness Center medical marijuana dispensary, which opened in 2006, on July 25, 2012 in Los Angeles. The Los Angeles City Council has unanimously voted to ban storefront medical marijuana dispensaries and to order them to close or face legal action.
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The Los Angeles City Council's effort to close down the city's medical marijuana dispensaries next week could face a serious challenge Wednesday, when activists say they will submit a petition with 50,000 signatures to overturn a recently approved ban.

The petition that will be turned over to the L.A. City Clerk's Office calls for a referendum next March on the new ordinance banning storefront dispensaries effective Sept. 6. But the petition's immediate effect will be to prevent the ordinance from even going into effect.

The City Council voted last month to ban the dispensaries, citing conflicting court opinions about whether the city can legally regulate cannabis collectives. While banning storefront dispensaries, the city will allow licensed patients or caregivers to grow and transport their own medical marijuana under the ordinance.

After the vote, the City Attorney's Office sent letters to 1,046 suspected dispensary locations, warning them to shut down by Sept. 6 — or face court action and a $2,500 fine for every day they remain open past the deadline.

Medical marijuana supporters quickly mounted a signature-gathering effort in hopes of forcing a referendum on the issue. A minimum of 27,425 signatures is required to get the issue on the ballot, according to petition- drive organizers, who say they've collected around twice that many.

Once the petition is submitted, the City Clerk's Office had three days to count signatures and 15 days to verify the signatures against voter registration information, according to Kim Briggs with the City Clerks Office's Election Division. During that 18-day period, the ordinance is suspended. If the petition qualifies, it will be sent to the L.A. City Council, which can repeal the ordinance, call for a special election in the next 110-140 days or put it on the March 5 ballot.

If placed on the ballot next March, the referendum on the ban will take place at the same time as Angelenos elect a new mayor.

Medical marijuana activists say, however, that they hope the Council revisits the idea of a total ban — in which case no referendum will be necessary.

"We want a strict regulatory system in place to ensure safe access for patients and a nuisance-free process for neighborhoods," referendum proponent Norma Schaffer said. "This one-size-fits-all ban not only hurts patients, but it eliminates dispensaries playing by the rules while doing little to shut down rogue dispensaries.

"We need good policy, not knee-jerk bans that make the problem worse," she said. "We're confident the voters of Los Angeles will agree with us."

On Aug. 17, a medical marijuana trade group called the Patient Care Alliance filed a lawsuit in hopes of blocking the marijuana ban, calling it a "reckless, baseless and heartless act of denial of necessary medical services."

One of the champions of the ban, Councilman Jose Huizar, said after the Council's vote in July that the city's action still provides safe access to marijuana for patients who need it, but also puts the city on solid legal footing and alleviates quality-of-life issues that constituents complain about.

"Relief is coming in the form of having a more focused and intense crackdown on these dispensaries that cause problems in our neighborhoods," Huizar said.

Councilman Paul Koretz, an ally of the medical marijuana community, advocates allowing 100 or so of the city's oldest dispensaries to remain open.

This story has been updated.

Correction: A previous version of this story stated that the signatures had to be verified before the ban would be prevented from going into effect, which is inaccurate.